My 16 year old cat is in ESRF (End Stage Renal Failure) and we are trying to keep her comfortable. She is anemic, so I ordered this Dong Quai to help her. It's only been two days since I've started her on this product and I've noticed a big improvement. The little girl has much more energy! She is up walking around instead of sleeping all the time. I'm quite surprised it has worked so fast!